The Study Of Robust Optimization For Liner Ship Route Schedule Design With Port Time Uncertainty

In recent years,due to the increasingly fierce competition in the shipping industry and the global shipping industry downturn,there is limited space for freight rate to grow,which lead to great decrease in liner companies’ revenue.In such situation,liner companies are seeking tools for developing reasonable schedules to control costs and increase revenue.However,in fact the service is not reliable as the imagination.There are many reasons for low liner schedule reliability.Port time uncertainty is the main reason.As a result,it is crucial to take full account of the port uncertaintywhen developing schedules.According to the Ministry of Transport issued by the highway waterway transportation energy-saving emission reduction "second five" plan to 2005 as the basis for the year 2015,the operating unit emissions of operating units will reduce carbon dioxide emissions by about 16%.At the same time,with the rapid development of the maritime industry,the number of ships increased significantly,ship carbon emissions as one of the sources of greenhouse gases,a huge impact on the global environment.According tothe requirements of the Kyoto Protocol,from the beginning of 2012developing countries to bear emission reduction obligations.Due to the non-linear relationship between the fuel consumption and the speed of the ship,the speed of the ship’s voyage is reduced by the shipping companies in the short term to reduce the operating costs and increase the energy saving of the ships.This article aims to propose a schedule optimal design method of a single route with port time uncertainty.Firstly,analyze schedule reliability,delay factors and optimal aim.Assuming ports of call and port rotation are known,this article proposed a determined model to minimize the total cost.Secondly,based on the determined model,this article considered the port time uncertainty to build up a robust optimization model of liner shipping schedule design based on robust optimization methods present by Bertsimas and Sim.Finally,take a domestic shipping company AWE2 route as an example,this paper use Lingo to solve the problem and make a robustness analysis.In addition,in practical application of the model,the decision-makers can change the budget of uncertainty to regulate their risk appetite.